A woman testified Friday that she was stunned and confused when a friend told her a big blue plastic tub of concrete that he wanted to store at her house contained the remains of his ex-girlfriend.

Kalae Casorso told a jury hearing the murder case against Jason Omar Griffith that she demanded to know what was in the heavy tub of gray rocky material that Griffith and his roommate, Louis Colombo, were wheeling down a ramp from a U-Haul truck.

"I think he said something to the effect, 'It's not what you think,'" Casorso added.

Griffith, 35, is standing trial in Clark County District Court on charges that he killed "Fantasy" dancer Deborah Flores Narvaez in December 2010, sawed her legs off, and tried to dispose of the remains in tubs of crudely mixed concrete.

Casorso, a former girlfriend of Griffith, told prosecutor Michelle Fleck that she didn't call police because she feared what happened to the woman she knew as Debbie Flores could happen to her.

Casorso was one of several witnesses on the second day of testimony in a trial that is expected to continue through next week.

Griffith has pleaded not guilty to first-degree murder. His attorneys, Jeff Banks and Abel Yanez, say evidence will show that Flores had a history of violence against other boyfriends and against Griffith — and that Griffith was defending himself when Flores died.

Griffith could face life in prison if he's convicted.

Griffith and Flores each danced in Las Vegas Strip productions. Griffith was a dancer in the Cirque du Soleil show "Love" at Mirage. Flores, 31, performed in the "Fantasy" revue at Luxor.

Jurors have been told the two had a passionate and tempestuous relationship, and that Flores told people she was pregnant before she disappeared. However, medical examiners didn't find evidence of a pregnancy during her autopsy.

Prosecutor Marc DiGiacomo told the jury evidence would show that in the weeks preceding Flores' death, Griffith was having trouble juggling relationships with Flores and with another woman, a dancer in another Cirque show.

Fleck and DiGiacomo say Griffith choked Flores and asphyxiated her with a plastic bag over her head, then tried over several days to dispose of her body.

After Colombo was granted immunity and spoke with police, Griffith was arrested in early January 2011.

Flores' body parts were found in two tubs inside sealed closets in a vacant downtown Las Vegas home.